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121.
Iveta M. Petrova Martijn J. Malessy Joost Verhaagen Lee G. Fradkin Jasprina N. Noordermeer 《Molecular neurobiology》2014,49(1):303-315
The receptor tyrosine kinase-like orphan receptor (Ror) proteins are conserved tyrosine kinase receptors that play roles in a variety of cellular processes that pattern tissues and organs during vertebrate and invertebrate development. Ror signaling is required for skeleton and neuronal development and modulates cell migration, cell polarity, and convergent extension. Ror has also been implicated in two human skeletal disorders, brachydactyly type B and Robinow syndrome. Rors are widely expressed during metazoan development including domains in the nervous system. Here, we review recent progress in understanding the roles of the Ror receptors in neuronal migration, axonal pruning, axon guidance, and synaptic plasticity. The processes by which Ror signaling execute these diverse roles are still largely unknown, but they likely converge on cytoskeletal remodeling. In multiple species, Rors have been shown to act as Wnt receptors signaling via novel non-canonical Wnt pathways mediated in some tissues by the adapter protein disheveled and the non-receptor tyrosine kinase Src. Rors can either activate or repress Wnt target expression depending on the cellular context and can also modulate signal transduction by sequestering Wnt ligands away from their signaling receptors. Future challenges include the identification of signaling components of the Ror pathways and bettering our understanding of the roles of these pleiotropic receptors in patterning the nervous system. 相似文献
122.
Priscila R Moreira Marcos A Maioli Hyllana CD Medeiros Marieli Guelfi Flávia TV Pereira Fábio E Mingatto 《Biological research》2014,47(1)
Background
The liver is an important organ for its ability to transform xenobiotics, making the liver tissue a prime target for toxic substances. The carotenoid bixin present in annatto is an antioxidant that can protect cells and tissues against the deleterious effects of free radicals. In this study, we evaluated the protective effect of bixin on liver damage induced by carbon tetrachloride (CCl4) in rats.Results
The animals were divided into four groups with six rats in each group. CCl4 (0.125 mL kg-1 body wt.) was injected intraperitoneally, and bixin (5.0 mg kg-1 body wt.) was given by gavage 7 days before the CCl4 injection. Bixin prevented the liver damage caused by CCl4, as noted by the significant decrease in serum aminotransferases release. Bixin protected the liver against the oxidizing effects of CCl4 by preventing a decrease in glutathione reductase activity and the levels of reduced glutathione and NADPH. The peroxidation of membrane lipids and histopathological damage of the liver was significantly prevented by bixin treatment.Conclusion
Therefore, we can conclude that the protective effect of bixin against hepatotoxicity induced by CCl4 is related to the antioxidant activity of the compound. 相似文献123.
124.
G. I. El’chinova T. A. Vasilyeva L. A. El’kanova Yu. A. Revazova N. V. Petrova E. E. Timkovskaya R. A. Zinchenko 《Russian Journal of Genetics》2014,50(5):543-548
Using data on the distribution of frequent surnames, the Crow index and its components, and nine polymorphic DNA loci, it was shown that the Tatar population of the Republic of Tatarstan is divided into subethnic groups (Mishars, Teptyars, and Kazan Tatars). No subdivision within each of these groups was found. 相似文献
125.
Yu. V. Kuzmicheva A. I. Shaposhnikov T. S. Azarova S. N. Petrova T. S. Naumkina A. Yu. Borisov A. A. Belimov L. V. Kravchenko N. V. Parakhin I. A. Tikhonovich 《Russian Journal of Plant Physiology》2014,61(1):112-118
The qualitative and quantitative composition of low-molecular exometabolites in roots of pea (Pisum sativum L.) was studied with a cultivar Triumph and its parental forms (a symbiotically effective variety k-8274 and a modern highly productive cv. Classic). A relationship between root exudation and the ability of cultivars to establish symbiosis was analyzed. In the early stages of plant growth, the roots of cv. Triumph exhibited low exudation of organic acids, sugars, and amino acids. The quantitative composition of organic acids in the root exudates of cv. Triumph was close to that of cv. k-8274, whereas the composition of sugars and amino acids was similar to that of cv. Classic. In the field experiment, the effect of inoculation with a mixture of rhizobium strains and mycorrhizal fungus on plant growth was more evident in cv. Triumph than in cvs. Classic and k-8274. The results suggest that the high symbiotic potential of cv. Triumph is related to exudation of pyruvic and succinic acids that were the major components of root exometabolites both in Triumph and k-8274 cultivars. 相似文献
126.
Jean-Karim Hériché Jon G. Lees Ian Morilla Thomas Walter Boryana Petrova M. Julia Roberti M. Julius Hossain Priit Adler José M. Fernández Martin Krallinger Christian H. Haering Jaak Vilo Alfonso Valencia Juan A. Ranea Christine Orengo Jan Ellenberg 《Molecular biology of the cell》2014,25(16):2522-2536
The advent of genome-wide RNA interference (RNAi)–based screens puts us in the position to identify genes for all functions human cells carry out. However, for many functions, assay complexity and cost make genome-scale knockdown experiments impossible. Methods to predict genes required for cell functions are therefore needed to focus RNAi screens from the whole genome on the most likely candidates. Although different bioinformatics tools for gene function prediction exist, they lack experimental validation and are therefore rarely used by experimentalists. To address this, we developed an effective computational gene selection strategy that represents public data about genes as graphs and then analyzes these graphs using kernels on graph nodes to predict functional relationships. To demonstrate its performance, we predicted human genes required for a poorly understood cellular function—mitotic chromosome condensation—and experimentally validated the top 100 candidates with a focused RNAi screen by automated microscopy. Quantitative analysis of the images demonstrated that the candidates were indeed strongly enriched in condensation genes, including the discovery of several new factors. By combining bioinformatics prediction with experimental validation, our study shows that kernels on graph nodes are powerful tools to integrate public biological data and predict genes involved in cellular functions of interest. 相似文献
127.
Cyclic di-GMP is a conserved signaling molecule regulating the transitions between motile and sessile modes of growth in a variety of bacterial species. Recent evidence suggests that Pseudomonas species harbor separate intracellular pools of c-di-GMP to control different phenotypic outputs associated with motility, attachment, and biofilm formation, with multiple diguanylate cyclases (DGCs) playing distinct roles in these processes, yet little is known about the potential conservation of functional DGCs across Pseudomonas species. In the present study, we demonstrate that the P. aeruginosa homolog of the P. fluorescens DGC GcbA involved in promoting biofilm formation via regulation of swimming motility likewise synthesizes c-di-GMP to regulate surface attachment via modulation of motility, however, without affecting subsequent biofilm formation. P. aeruginosa GcbA was found to regulate flagellum-driven motility by suppressing flagellar reversal rates in a manner independent of viscosity, surface hardness, and polysaccharide production. P. fluorescens GcbA was found to be functional in P. aeruginosa and was capable of restoring phenotypes associated with inactivation of gcbA in P. aeruginosa to wild-type levels. Motility and attachment of a gcbA mutant strain could be restored to wild-type levels via overexpression of the small regulatory RNA RsmZ. Furthermore, epistasis analysis revealed that while both contribute to the regulation of initial surface attachment and flagellum-driven motility, GcbA and the phosphodiesterase DipA act within different signaling networks to regulate these processes. Our findings expand the complexity of c-di-GMP signaling in the regulation of the motile-sessile switch by providing yet another potential link to the Gac/Rsm network and suggesting that distinct c-di-GMP-modulating signaling pathways can regulate a single phenotypic output. 相似文献
128.
S. A. Alen’kina L. P. Petrova M. K. Sokolova M. P. Chernyshova K. A. Trutneva V. A. Bogatyrev V. E. Nikitina 《Microbiology》2014,83(3):262-269
The lectins of associative nitrogen-fixing bacteria Azospirillum brasilense Sp7 and its mutant A. brasilense Sp7.2.3 were shown to have different effects on the components of the wheat seedling root signal system, namely to regulate the levels of cAMP, nitric oxide, diacylglycerol, and salicylic acid, as well as to induce the activities of superoxide dismutase and lipoxygenase. Our results make it possible to consider azospirilla lectins as inducers of the signal systems in wheat seedling roots, since they cause development of several flows of primary signals. These data are of general biological importance, since lectins are present in all living organisms and most of the functions of lectins remain insufficiently understood. 相似文献
129.
I I Kruman S G Kolaeva E N Iljasova G N Zubrikhina V N Khachko A S Petrova 《Comparative biochemistry and physiology. B, Comparative biochemistry》1986,83(1):173-177
The conditions for obtaining crypt cells from ground squirrel small intestine were chosen which allow flow-through cytofluorometric analysis of the DNA synthesis of this tissue. DNA synthesis was found to be greatly reduced in the intestinal crypt cells of ground squirrel during deep hibernation in torpid animals, in animals during spontaneous arousals and in animals prevented from hibernation. The conclusion is made about endogenous control of the DNA synthesis in the cells of true hibernators. 相似文献
130.